Method of treating a packaging element, especially for medical or pharmaceutical use; packaging element thus treated

Abstract

The present invention relates to a method of treating a packaging element,specially a sealing element, comprising the coating with a polymer film of at least those parts of said element which are liable to be in contact with the products packaged, wherein said coating is produced by polymerization, assisted by cold-far-remote-plasma, of at least one monomer chosen from siloxanes and silazanes of formula: ##STR1## in which: A represents an oxygen atom or the NH group and; R 1 , R 2 , R 3 , R 4 , R 5 and R 6 represent, independently, a hydrogen atom or an alkyl or alkoxy group having from 1 to 4 carbon atoms, preferably a methyl group. Application: stoppers intended for a medical or pharmaceutical use.

What is claimed is: 
     
       1. A method of treating a packaging element, comprising the coating with a polymer film of at least a portion of said element, wherein said coating is produced by cold-far-remote-plasma-assisted polymerization of at least one monomer in gaseous form selected from the group consisting of siloxanes and silazanes of formula: ##STR4## in which: A represents an oxygen atom or the NH group and; R 1 , R 2 , R 3 , R 4 , R 5  and R 6  represent, independently, a hydrogen atom or an alkyl or alkoxy group having from 1 to 4 carbon atoms.   
     
     
       2. The method as claimed in claim 1, wherein said portion of the packaging element is made of a material selected from an elastomer and a thermoplastic. 
     
     
       3. The method as claimed in claim 1, wherein the packaging element is a sealing element. 
     
     
       4. The method as claimed in claim 1, wherein the packaging element is selected from the group consisting of a bottle stopper, a disk, a washer, a syringe plunger tip, a needle and syringe protection device. 
     
     
       5. The method as claimed in claim 1, wherein the plasma is a nitrogen plasma. 
     
     
       6. The method as claimed in claim 1, wherein the polymerization is carried out in the presence of gaseous oxygen as a polymerization cofactor. 
     
     
       7. The method as claimed in claim 6, wherein oxygen is used in an amount by volume lying between 0% and 50%, of the volume of a plasma-generating gas used to form the plasma. 
     
     
       8. The method as claimed in claim 1, wherein the polymer film has a thickness lying between 100 Å and a few microns. 
     
     
       9. The method as claimed in claim 8, wherein the polymer film has a thickness lying between 100 and 10,000 Å. 
     
     
       10. A method of treating a packaging element comprising coating at least a portion thereof with a polymer film, said coating being produced by cold-far-remote-plasma assisted polymerization of tetramethyldisiloxane in gaseous form. 
     
     
       11. A method of treating a packaging element comprising: a) introducing the packaging element into a polymerization chamber;   b) introducing into the polymerization chamber at least one monomer in gaseous form selected from the group consisting of siloxanes and silazines of formula: ##STR5## wherein A is an oxygen atom or NH group; and R 1 , R 2 , R 3 , R 4 , R 5  and R 6  are, independently, a hydrogen atom or an alkyl or alkoxy group having from 1 to 4 carbon atoms;   c) introducing a plasma generating gas into a discharge zone remote from the polymerization chamber and transferring energy to the plasma generating gas to cause the formation of excited species;   d) passing said excited species into the polymerization chamber to cause said monomer to polymerize and deposit a polymer film on said packaging element; and   e) removing said packaging element with polymer film thereon from said polymerization chamber.   
     
     
       12. A packaging element having a polymer film coating on at least a portion thereof, said coating being produced by cold-far-remote-plasma assisted polymerization of at least one monomer in gaseous form selected from the group consisting of siloxanes and silazines of formula: ##STR6## wherein A is an oxygen atom or NH group; and R 1 , R 2 , R 3 , R 4 , R 5  and R 6  are, independently, a hydrogen atom or an alkyl or alkoxy group having from 1 to 4 carbon atoms. 
     
     
       13. A packaging element, as claimed in claim 12, which is a sealing element.